The present invention relates to an aerodynamic toy of the type which is thrown by the user.
A large number of aerodynamic toys of this type are well known and can be readily seen at recreational sites, such as beaches, parks or school playgrounds. A variety of these devices are disclosed in U.S. Pat. Nos. 2,659,178, 2,835,073, 3,580,580 and 3,590,518.
Toys of this type are usually made of molded plastic discs which are thrown or launched for flight by gripping the disc with the thumb on the convex outer side thereof and with one or more fingers on the concave inner surface of the unit. It is thrown by using an underhand or sidearm motion with a snapping action of the wrist. This causes the disc to spin and the direction of flight is determined by the angle at which the disc is released with respect to the horizontal plane.
U.S. Pat. No. 3,828,466 discloses an aerodynamic device of this type which consists of a plurality of inter boundary rings projecting down from relatively flat plateau upper outer surfaces and which has raised dimples which make for a more comfortable hand grip and better control of the device when thrown.
U.S. Pat. No. 3,855,728 teaches an aerodynamic toy which includes one disc nested within another disc and which are thrown at the same time and which separate during flight so that both land in the same vicinity.
Typical flying disc type devices such as those disclosed in U.S. Pat. Nos. 356,929, 3,359,678 3,724,122 and D 183,626 are designed with a number of circular raised ribs spaced apart on the convex side of the device. These ribs are placed on the device to create turbulence on the convex side which will decrease pressure on that side and create a lifting action. These devices are typically thin in the center section and thicker on the outside rim. Examples of this type are shown in U.S. Pat. Nos. 3,359,678 and 4,045,029. The disadvantage of these rings on the outer surface of the device is that it causes an increase in drag and creates an annoying whistling sound in flight.